A094178 Numbers n such that 4n+1 is divisible only by primes of form 4m+1 (i.e., by the Pythagorean primes A002144).

1, 3, 4, 6, 7, 9, 10, 13, 15, 16, 18, 21, 22, 24, 25, 27, 28, 31, 34, 36, 37, 39, 42, 43, 45, 46, 48, 49, 51, 55, 57, 58, 60, 64, 66, 67, 69, 70, 72, 73, 76, 78, 79, 81, 84, 87, 88, 91, 93, 94, 97, 99, 100, 102, 105, 106, 108, 111, 112, 114, 115, 120, 121, 123, 126, 127

Offset

1,2

Comments

For the actual numbers 4n+1, see A008846(n).

Complement of A124934; A125203(a(n)) = 0; A000290 and A000217 are subsequences. - Reinhard Zumkeller, Nov 24 2006

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Prog

(Haskell)
import Data.List (elemIndices)
a094178 n = a094178_list !! (n-1)
a094178_list = map (+ 1) $ elemIndices 0 a125203_list
-- Reinhard Zumkeller, Jan 02 2013

Crossrefs

Sequence in context: A292987 A352719 A187580 * A085795 A068675 A190858

Adjacent sequences: A094175 A094176 A094177 * A094179 A094180 A094181

Keyword

nonn

Author

Lekraj Beedassy, May 06 2004

Extensions

More terms from Ray Chandler, Jun 20 2004

Status

approved